class_docstr: This plan is used for storing information required for order by
  operations.
  
  Arguments:
      orderby_list: List[(TupleValueExpression, EnumInt), ...]
          A tuple of the column names string and the type of sort in the plan
code: def sort_types(self):
      return [_[1] for _ in self._orderby_list]
  
file_path: evadb/evadb/plan_nodes/orderby_plan.py
imports: from evadb.plan_nodes.abstract_plan import AbstractPlan
  from evadb.plan_nodes.types import PlanOprType
label_desc: Use image node_id 3 for calling the OrderByPlan obj's underlying member method code with example usage: obj.sort_types() and returns: unknown